The New Zealand Institute for Plant & Food Research Limited. Xylella fastidiosa: A pathogen with the X-factor

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1 Xylella fastidiosa: A pathogen with the X-factor Myrtle Rust Symposium, 28 August 2017

2 The pathogen Xylella fastidiosa» X. fastidiosa (Xf) is a gammaproteobacterium.» Xf is comprised of four subspecies.» Xf is unusual in that it can multiply within most plant species.» Xf colonises the xylem vessel of plants, restricting water movement.» Blocked xylem are associated with development of disease symptoms based on plant physiological responses to water stress. (Almeida & Nunney 2015)

3 X. fastidiosa has a wide host range (CIHEAM Newsletter No. 33 June 2015)» Based on 2015 data, the host range comprises plants in more than 68 families, 187 genera and 300 plant species. Not all hosts are associated with each subspecies and not all show symptoms.

4 X. fastidiosa has a large number of vectors» Xf is exclusively transmitted by xylem sap-feeding insects of the order Hemiptera, sub-order Auchenorrhyncha. Hordnia atropunctata Philaenus spumarius Diceroprocta apache

5 X. fastidiosa has broad geographical distribution» Xf has been reported over a large range of climatic environments.

6 X. fastidiosa has a dramatic impact on production systems globally Grapevine scourge has returned to Temecula Valley s Wine Country 17 August 2017, The Press-Enterprise California vine disease (now known as Pierce s disease) was observed in the US in the 1880s. Introduction of a new vector, the glassy-winged sharpshooter caused a devastating outbreak in the late 1990s. Pierce s disease costs California approximately $104.4 million per year.

7 Bacteria destroying Puglia's precious olive groves could ruin Italy's oil industry 22 Aug 2017, The Telegraph Xf was detected in olive trees in Lecce province in Apulia, Italy, in October The outbreak was likely due to importation of infected coffee plants. Puglia accounts for 180,000 tonnes of the total 480,000 tonnes of olive oil exports annually. Xf has infected trees across 74,000 acres. Eight months before it was spread across just 20,000 acres.

8 Xylella fastidiosa threatens Andalusia 7 July 2017, Olive Oil Export In November 2016, Mallorca declared the first detection of Xf on sweet cherry in Spain. In June 2017, Xf was detected on the mainland for the first time in almond trees in the massive oliveproducing region of Valencia. Spain produces roughly half of the world s supply of olive oil. In Mallorca, Xf was detected for the first time in Common Fig recently.

9 Why is it a threat to New Zealand?

10 Why is it a threat to New Zealand?

11 What are the most likely pathways for entry into NZ? Exotic vectors (e.g. Glassy-winged sharpshooter) Imported plant material (e.g. Ornamentals, Vitis, cut flowers?) (NZ border) Susceptible plants (e.g. Grapevine) Extant vectors (e.g. Meadow Spittlebug)

12 What is in place to mitigate the threat to New Zealand?» Mandatory testing is already in place for tissue cultures of known hosts Vitis, Vaccinium, Fragaria, and Rubus.» In December 2016, MPI amended the nursery stock Import Health Standard» Whole plants, cuttings, and dormant bulbs.» Acacia, Acer, Acrocomia, Aesculus, Arbutus, Asparagus, Bidens, Canna, Carya, Carya ovata, Castanea, Cotoneaster, Delphinium, Diospyros, Eucalyptus, Eugenia, Eupatorium, Fagus, Fagus sylvatica, Ficus, Fuchsia, Hebe, Humulus, Hydrangea, Ipomoea batatas, Juglans, Metrosideros, Nandina, Phoenix, Photinia, Platanus, Populus, Pseudotsuga, Quercus, Ranunculus, Rosa, Salix, Solidago, Ulmus, and Verbena.

13 » The European Union has called Xylella fastidiosa one of the most dangerous plant pathogens on earth.» Xylella fastidiosa is number 1 on Australia s Top 40 national priority plant pests list.».some voices in the "Xylella hoax" faction have charged that the EU-mandated campaign to eradicate Xylella-infected olive trees is part of a scheme to eliminate traditional cultivation methods andrew.pitman@plantandfood.co.nz